<template>
  <div class="mt-3 btn-container">
    <div class="btn-group" role="group" aria-label="Basic example">
      <button type="button" class="btn" :class="active === 0 ? 'btn-primary' : 'btn-secondary'" @click="onBtnClick(0)">全部</button>
      <button type="button" class="btn" :class="active === 1 ? 'btn-primary' : 'btn-secondary'" @click="onBtnClick(1)">已完成</button>
      <button type="button" class="btn" :class="active === 2 ? 'btn-primary' : 'btn-secondary'" @click="onBtnClick(2)">未完成</button>
    </div>
  </div>
</template>

<script>
export default{
    name:'TodoButton',
    emits:['update:active'],
    props:{
        active:{
            type:Number,
            required:true,
            default:0,
        }
    },
    methods: {
        onBtnClick(index){
            if(index===this.active){
                return this.$emit('update:active',index)
            }
        }
    },
}
</script>

<style lang="less" scoped>
.btn-container {
  width: 400px;
  text-align: center;
}
</style>